English Abstract

All-cellulose Nanocomposites using Cellulose Nanofibers

Graduate School of Engineering, Kobe University, Nada, Kobe, Japan
Nippon Gomu Kyokaishi,(2013),86(2),28-34 General Review in Japanese

All-cellulose nanocomposites, in which reinforcement nanofiber and matrix are both composed of cellulose, were fabricated using various processes and various resources such as kenaf bast fiber, canola fiber, filter paper and bacterial cellulose. The structure and mainly mechanical properties of these novel composites were reviewed. By grinding, plant microfiber (fiber diameter of ca. 30 μm) could be down sized to nanofiber (fiber diameter of ca. 30 nm) without destroying the crystallites of cellulose I. By immersing these nanofibers into solvent, their surface was selectively dissolved. Then, by compression and drying, all-cellulose nanocomposite was obtained. The nanocomposites reveal superior mechanical properties (tensile strength up to 411 MPa) and optical transparency. Direct fabrication method starting from microfiber into nanocomposite was also proposed through nanowelding using ionic liquid as solvent. Cellulose nanopaper from cellulose nanofiber was also mentioned as a high tough material. These high mechanical performance of these novel nanomaterials are originated form three factors, that is, high mechanical performance of cellulose itself, strong hydrogen bonds between nanofibers, and high entangled state of nanofibers.

Keywords: all-cellulose composite, cellulose nanofiber, nanopaper, ionic liquid, mechanical property